[tor-bugs] #30206 [Obfuscation/Snowflake]: Segfault in proxy-go

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#30206: Segfault in proxy-go
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 Reporter:  irl                    |          Owner:  cohosh
     Type:  defect                 |         Status:  needs_revision
 Priority:  Medium                 |      Milestone:
Component:  Obfuscation/Snowflake  |        Version:
 Severity:  Normal                 |     Resolution:
 Keywords:                         |  Actual Points:
Parent ID:                         |         Points:
 Reviewer:                         |        Sponsor:
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Changes (by cohosh):

 * status:  accepted => needs_revision


Comment:

 Here's a fix: https://github.com/cohosh/snowflake/compare/ticket30206

 The proxy-go instances were seg faulting occasionally in cases where the
 client successfully made a data channel connection but the data channel
 was closed before the timeout occurred.

 I added a second channel that will trigger when the data channel has been
 successfully opened (and therefore pc.Destroy() is handled by
 dataChannelHandler), and only destroy the connection if this channel has
 not been closed before the Timeout (which I've shortened to a more
 realistic time).

 I'm going to patch our deployed proxy-go instances immediately, but wait
 to merge until this has been reviewed.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/30206#comment:3>
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